Pili multigemini is an uncommon hair condition also called compound hair follicles or pili bifurcati. A person with this disorder will notice several strands of hair that appear to be growing from a single hair follicle. It is usually present on the scalp of children and infants, and the facial hair of men. The cause of pili multigemini is unknown, although there may be a genetic link. Treatment for this condition focuses on the removal of the affected hair follicles to present the appearance of uniform hair growth.
Diagnosis of pili multigemini may occur after a physician makes a visual examination of the scalp and hair. Three or more strands of hair are commonly observed growing out of a single hair follicle. Some men have been diagnosed with pili multigemini of beard and facial hair, it has sometimes been located on the hairs on the back of males. The follicles with multiple strands exiting from them may appear in a linear formation on the face or the back.
Extreme cases of pili multigemini have been observed where as many as 36 strands of hair were observed exiting from one hair follicle. Less severe cases have been reported where the patient had an average of 20 hairs growing out of each follicle. Most people with pili multigemini average 3 to 10 hairs per hair cluster.
Under microscopic examination, multiple strands of hair do not grow out of one hair follicle. The roots of several hair follicles are clustered together below the scalp. These strands of hair group together to exit from the scalp through a single hair canal. Normal hair grows from a single hair follicle and exits from one hair canal to the surface of the scalp.
Another pili multigemini symptom is the abnormal depth of the hair follicle within the scalp tissue. The roots are buried further within the scalp than normal hair follicles, making plucking the hairs difficult. Hair that is affected by this condition may be more coarse and curly than other normally growing hairs.
There are few treatments for pili multigemini. Electrolysis to destroy the affected hair follicle may be used if the appearance of the hair growth is unsightly. Some patients undergo cryosurgery to remove the hair follicles exhibiting signs of the condition. A simple method some people use is to shave the specific hair follicles that are growing more than one hair strand at a time.